Tracking an FDA advisory panel’s meeting on J&J’s Covid-19 vaccine

February 26, 2021 steven

Now it’s Johnson & Johnson’s turn.

A panel of outside experts is meeting Friday for a third time to consider whether the Food and Drug Administration ought to give an emergency use authorization for a Covid-19 vaccine, this one from J&J. And for a third time, STAT reporters will live-blog the advisory committee’s deliberations.

The J&J vaccine could be a potential game changer, at least in some areas. Made by J&J’s vaccine division, Janssen Pharmaceuticals, it is a single-dose vaccine that does not need to be frozen when it is shipped and distributed. The vaccine is what’s known as “fridge stable,” meaning it can be shipped and stored at the temperature of a regular refrigerator. Both those characteristics will make this vaccine much easier to deploy if the FDA authorizes its use.

The two vaccines already in use in the United States, from Moderna and the Pfizer-BioNTech partnership, are both two-dose vaccines with onerous cold-chain requirements.

It’s hard to imagine the panel meeting to assess the vaccine, known as the Vaccines and Related Biological Products Advisory Committee or VRBPAC, won’t recommend that the FDA issue an EUA for the J&J vaccine.

But it is conceivable that the committee might recommend the vaccine only be used in people 18 to 75, because there were too few data generated by the J&J Phase 3 study to determine if the vaccine works in people over the age of 75. Neither of the two earlier authorized vaccines had an age cap placed on their EUAs.

Regulatory authorities in Europe and Britain faced a similar dilemma when they authorized AstraZeneca’s vaccine for use. (The company’s U.S. clinical trial is still ongoing.) But in both cases, they concluded that data gathered in Phase 2 trials — which charted the immune responses of people who had been vaccinated — were sufficient to assume the vaccine would work in the elderly. The World Health Organization has comes to the same conclusion in giving an emergency use listing to AstraZeneca’s vaccine.

It will be interesting to see if assumptions based on immunological data are sufficient for the VRBPAC members to recommend J&J’s vaccine for use in the elderly — and if they do recommend it, whether the FDA accepts the recommendation. The FDA generally follows VRBPAC’s advice, but it is not required to do so.

The J&J vaccine hasn’t been tested yet in children and teens under the age of 18, so it will not be authorized for use in them.

The J&J vaccine was found to reduce cases of moderate to severe Covid infection by 66.1%, starting 28 days after the single shot. (It takes a while for the protection of the vaccine to build up.) Results released in late January suggested the vaccine worked better in some areas than others; in the U.S., the vaccine was 72% protective.

An FDA analysis of the J&J data, released on Wednesday, suggested the vaccine was a little less effective against a virus variant first spotted in South Africa, known as B.1.351. But its protection did not appear to be eroded by a variant first spotted in Brazil, known as P.2.

The United States has purchased 100 million doses of the J&J vaccine, but supplies are expected to be scarce until at least April.

Our live coverage of the meeting is below. We’ll be posting updates and analysis throughout the day, in reverse chronological order.

New data drive home the threat from coronavirus variants

10:30 a.m.: Adam MacNeil, an epidemiologist at the Centers for Disease Control and Prevention, showed the panel new data on the three SARS-CoV-2 variants researchers have been most worried about: B.1.1,7, B.135.1, and P.1. The grim message: Variant strains of the virus are dangerous and widespread.

All three of those variants have been detected in the U.S. “We have to assume in the absence of other information that these variants probably could exist throughout the entire U.S.,” he said.

The B.1.1.7 variant has become the predominant strain in the U.K. and in much of Europe. MacNeil presented conclusions from unpublished data reviewed by the New and Emerging Viruses Threats Advisory Group that deaths and hospitalizations were 1.7 times higher with the new variant, which are thought to have arrived in the U.S. in November. In models, a scaling up of vaccination could blunt the increase in cases from the variant.

B.135.1 is worrisome because it has shown the potential to reinfect previously infected or vaccinated people in some cases. (This means that the vaccines would become less effective, but would still protect against Covid-19.) MacNeil showed data from Zambia in which the B.135.1 variant, previously undetected, drove a 16-fold increase in cases in one month.

P.1. also seems to be able to overcome immunity. He described the experience in Manaus, Brazil, where an epidemic resulted in 76% of people having been infected. The emergence of P.1 resulted in a new spike in hospitalizations there, despite this apparent herd immunity.

MacNeil also said that right now, the U.S. is “nowhere close” to having herd immunity. The U.S. surveillance effort is scaling up, but it is still not at the scale needed to quickly identify new variants. He also emphasized that current strategies, like masking and social distancing, work and that vaccines, even with decreased effectiveness, vaccinations could still provide partial protection.

—Matthew Herper

Ho-hum?

9:35 a.m.: Has the excitement gone out of the prospects of emergency use authorizations for new Covid-19 vaccines? I ask because there are about 1,900 people watching the J&J hearing right now.

During the first VRBPAC hearing for a Covid vaccine, the Dec. 10 meeting on Pfizer and BioNTech’s vaccine, there were more than 15,000 people watching at points in the day.

— Helen Branswell

The path forward

8:10 a.m.: It seems a sure bet the VRBPAC will recommend that the FDA authorizes the J&J vaccine, and that FDA will do it quickly — as early as Saturday, perhaps.

Why do we think so? For one thing, the agency moved rapidly to issue EUAs for the Pfizer and Moderna vaccines. For another, the expert panel that issues recommendations to the Centers for Disease Control and Prevention on how vaccines should be used is meeting in an emergency session on Sunday to discuss the J&J vaccine. That group, the Advisory Committee on Immunization Practices, or ACIP, makes recommendations only after the FDA authorizes use of a vaccine. So, its Sunday meeting is a pretty solid clue.

If the FDA authorizes the J&J vaccine on Saturday and ACIP issues recommendations on Sunday, supplies of the vaccine could start to ship almost immediately. But as we said earlier, J&J doesn’t have a ton of vaccine to plug into the pipeline at this point. We’re hearing amounts in the very low millions of doses until April.

The vaccine will be entering the distribution program at a time when 46 million Americans have had a least one dose of vaccine and 21.5 million have received two doses — 8.4% of the population over 18 years of age.

It also comes at a time when new cases are declining and shortly after the country hit an ignominious mark — the U.S. death toll from Covid topped 500,000 people.

— Helen Branswell

VRBPAC’s agenda

7 a.m.: Good morning, STAT readers.

Your VRBPAC live-bloggers today are Matthew Herper and me, Helen Branswell.

For starters, let’s introduce you to the committee members. The FDA has a very strict conflict of interest policy for VRBPAC members. Anyone involved in any of the Covid-19 clinical trials — even a member who works at a university that is a trial site is “conflicted out,” which means that temporary replacements who are equally stringently vetted are named to sit in their place. Most of the members of today’s panel sat when VRBPAC evaluated the earlier two Covid vaccines.

The early part of the meeting, which begins at 9 a.m. EST, is mostly housekeeping. There’s a presentation on what emergency use authorizations are, and one on what surveillance data are indicating about the safety of the two Covid vaccines currently in use. There is also a session on the various virus variants — say that three times fast! — that are circulating and raising concerns about vaccine efficacy.

At 11:10 a.m. EST, a team from J&J will present their take on the data on their vaccine and will be questioned on it by committee members. After lunch — if there is a lunch break, VRBPAC meeting sessions often run long — FDA scientists will present their review of the data. And then VRBPAC members will be asked one or several questions by the FDA and will take one or several votes.

The meeting is meant to conclude at 5:30 pm. EST. We’ll see.

— Helen Branswell

Correction: An earlier version of this story misstated the number of Americans who have received at least one dose of Covid vaccine.

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